On the mornings of January 9, 10 and 11, 2021, you can watch as the waning crescent moon sweeps past a bright star – Antares in the constellation Scorpius – and an even brighter planet, Venus. Look east before the sun comes up. You can’t miss them if your sky is clear.
Antares is a red star and represents the Scorpion’s Heart. We in the Northern Hemisphere consider it a summer star, because it’s visible on summer evenings. But it’s up before the sun on cold northern winter mornings. Skywatchers in the Southern Hemisphere can see this star even better than we in the north. From there, it make a grand high arc across the sky. For a specific view of Antares, the moon and Venus on these January mornings, from your location on the globe, try Stellarium.
If you contrast the star Antares with the planet Venus, you’ll find that Antares twinkles fiercely, while Venus shines more steadily. But Venus might be twinkling a bit now, too, because it’s getting so low in the sky before the sun comes up. Venus is much closer to the sun on our sky’s dome than it was a few months ago. And it’s not going to get any higher in the predawn sky between now and sometime in February, when it’ll disappear into the sun’s glare.
So enjoy Venus while you can! It’ll be gone from our sky from about late February to about late April.
Throughout January 2021, Venus’ angular distance from the sun – its distance from the sun on our sky’s dome – will continue to shrink. Day by day, watch for Venus to sink deeper and deeper into the brightening glow of morning twilight.
Venus is appearing closer to the sunrise each day now because – in its smaller and faster orbit around the sun – this planet is about to “turn the corner” ahead of us in orbit. In other words, Venus is about to pass on the far side of the sun from Earth. It’ll be most nearly behind the sun, at superior conjunction as viewed from Earth, on March 26.
Then Venus will return – to our evening sky this time – in May, appearing near the western horizon as a surprisingly bright evening “star.”
By the way, we’re starting to collect photos of Venus as it descends into the dawn. If you get a good photo, submit it here.
Want more about the planets? Visit EarthSky’s monthly planet guide.
Bottom line: In January 2021, you can still see Venus easily above the sunrise glare. The moon will be sweeping past Venus and the red star Antares on the mornings of January 9, 10 and 11. Then watch over the coming weeks, as Antares ascends in the predawn sky, while Venus inches closer to the sunrise and finally disappears in the glare of morning twilight.